Characteristics of transtensional strike-slip faults and its controlling effect on hydrocarbon accumulation in Wuerhe area,Karamay,Xinjiang
Wuerhe bituminous vein is a small left-lateral strike-slip fault zone situated above the Wuerhe nasal uplift of the Wuxia fault zone in the northwest margin of the Junggar Basin.Following its formation,no significant transformation occurred,and vein-type bitumen deposits have developed within the fault zones.With favorable outcrop geological conditions and comprehensive three-dimensional seismic coverage,this area serves as a natural laboratory for studying strike-slip faults and reservoir control characteristics.In this study,UAV 3D modeling technology is employed to quantitatively analyze and dissect the outcrop of the strike-slip fault zone,combined with field section measurements.Seventeen faults are revealed in the fault zone,exhibiting a geese-like pattern on the northwest side of the main fault and a horsetail-like pattern on the southeast side,resulting in an overall negative flower-shaped fault zone.These results indicate that the formation of the faults can be attributed to Yanshanian sinistral shear stress within a tension-torsion environment influenced by tensile stress.The fracture cavity and induced fractures,particularly the active disk fracture,are well-developed.The opening of the cavity is positively correlated with the width of oil and gas infiltration.Based on the analysis of the relationship between transtensional strike-slip faults and reservoirs in Tarim Basin,it is believed that these faults serve as excellent vertical channels for hydrocarbon migration,active disks act as conduits while passive disks function as seals,traps located adjacent to active-disk of strike-slip faults represent ideal areas for oil and gas accumulation.
Northwestern margin of Junggar BasinWuxia fault beltWuerhe bituminous veinTranstensional strike-slip faultsReservoir control
国家科技期刊平台
NSTL
万方数据
